Problem behaviors such as school misconduct, underachievement, and dropout; tobacco, alcohol, and other drug use; violence and delinquency place youth at an increased risk for school failure, involvement in the criminal justice system, and chronic substance abuse. This study employs a randomized quasi-experimental design to test the protective effects of exposure to a social skills curriculum, enhanced school environment, and parent education in the special intervention group compared to problem behavior in a comparison group receiving usual education only. Approximately 2 cohorts totaling 2700 students in 7 middle schools were followed through the 6th, 7th, 8th and 9th grades. Approximately half received the special intervention. In multi-variate analyses association with problem behaving peers and low levels of self control consistently have been found to be risk factors, and parent monitoring and parent expectations for behavior have been found to be protective factors. Bivariate analyses of the efficacy of the intervention have revealed few, very modest effects which have not held in multivariate analyses. Data analyses are ongoing.